Weight Loss Dynamics

Why A Popular Piece Of Conventional Weight-Loss Wisdom Is Fundamentally Flawed.

- Pedro van Gaalen

If you’ve ever tried to lose weight before, you’ve undoubtedly heard of the 500-calorie-a-day deficit rule. It is a theory based on the concept of energy balance, one where all calories are considered equal, which states that a 3,500-calorie deficit is needed to lose one pound (0.45kg) of body weight.

This theory first gained traction in 1958 when Dr Max Washnofsky wrote a paper in the American Journal of Clinical Nutrition that concluded that “3,500 calorie is the caloric value of one pound of body weight lost”. It has since been the basis of conventional weight loss wisdom among health and fitness professionals for some five decades.

This theory also gave rise to the 500-calorie-a-day deficit guideline as it neatly broke that ‘magical’ figure of 3,500 into seven – seven days in a week to deliver sustainable, healthy weight loss of up to 0.45kg a week, and 2kg a month.

COMPLEX PROCESS

However, we now know that there are glaring faults with this theory, the most notable of which is the assumption that weight loss will continue in a linear fashion over time. This basically suggests that if you keep creating a 500-calorie-a-day deficit you’ll lose weight indefinitely, right? Well, not quite.

You see, the body doesn’t operate in such a simplistic manner. It is dynamic, and a change in one part of a system always results in changes in other parts. Accordingly, the real-world application of the energy balance theory is often far removed from the controlled lab environment where a pound of body mass will liberate 3,500 calories of energy in accordance with the first law of thermodynamics.